The invention relates to a method for operating road rollers, primarily bitumen road rollers, by means of an operating lever, at an adjustable maximum speed achieved with adjustable acceleration and with which the forward or reverse driving direction is selected with a switch arranged so the road roller is automatically brought to standstill, at an adjustable deceleration, when the driving direction is switched from forward to reverse, whereupon the driving direction reverses, and the speed automatically increases at the preset acceleration until the preset maximum speed is reached. The corresponding procedure is used to change roller direction from reverse to forward drive. The operating lever is moveable from a neutral position to a position for maximum speed and the change in direction (forward/reverse) is selected with the switch. When necessary, the road roller can be stopped by moving the lever to the neutral position.
After a 20 to 100 meter stretch of road has been coated with bitumen, a bitumen road roller drives back and forth over the coating 2 to 8 times. This procedure requires frequent changes in the roller's driving direction. Here, maintaining an even speed as well as braking and accelerating at slow rates are essential to satisfactory compaction. Rapid deceleration and acceleration rates increase the risk of bitumen shearing with persistent cracks and impressions in the bitumen as a result.
As known, construction vehicles are equipped with operating levers to control a vehicle's steering to the right or to the left. The lever is equipped with a switch for selecting steering to the right or to the left and operates within a deflection range in which lever deflection is proportional to the vehicle's speed. The change from forward to reverse is made with a switch integrated into the lever. These prior art operating levers depend on the judgment and skill of the vehicle operator and the acceleration, deceleration and maximum speed of the vehicle depend on the speed at which the lever is moved to its maximum deflection. In bitumen rolling, it is especially important, as previously noted, for the road roller to accelerate and brake at slow rates and at an even speed. The driving speed of the road roller must also be kept constant at a rate selected for the operation to yield satisfactory compaction.